Packet sending method, network node, and system

A controller, comprising a processor and a memory, the controller adapted to perform the steps of:

• obtaining a node latency of the first network node and a node latency of the second network node, wherein each node latency comprises a packet processing latency and a packet sending latency;
• obtaining a link latency of a link on the forwarding path;
• obtaining a cycle duration of the first network node and a cycle duration of the second network node;
• determining a first cycle number at which the first network node forwards a packet based on the cycle duration of the first network node and further determines a second cycle number at which the second network node forwards the packet, the second cycle number based on the cycle duration of the first network node;
• determining a first adjacent segment identifier corresponding to the first cycle number and a second adjacent segment identifier corresponding to the second cycle number, wherein the packet is in the service flow;
• wherein each network node has a packet receiving queue and a packet sending queue and each network node further has a clock, wherein the packet receiving queue and the packet sending queue exchange their roles after a fixed-length period of time, the fixed-length period of time being defined as a cycle, wherein sending of a packet in the packet sending queue is completed once in the cycle;
• generating a label stack, wherein the label stack comprises sequentially, from a top of the stack to a bottom of the stack, the first adjacent segment identifier and the second adjacent segment identifier;
• and
• sending the label stack to the first network node, wherein the label stack is used to indicate the first network node to forward the packet via the forwarding path within a period of time corresponding to the first cycle number.

A first network node for use in cyclic queuing and forwarding CQF, comprising

• an obtaining unit configured to obtain a packet and obtain a first label stack based on the packet, wherein the first label stack is a label stack corresponding to a forwarding path for forwarding the packet, the first label stack comprises an adjacent segment identifier of the first network node and an adjacent segment identifier of a second network node, the first network node being an ingress node of the forwarding path, and the second network node being an intermediate node of the forwarding path, and further wherein the first network node, the second network node, and the third network node are located is a segment routing network;
• wherein a correspondence between each adjacent segment identifier and a cycle time number is established wherein an outbound interface of each network node corresponds to a plurality of adjacent segment identifiers, and a segment identifier corresponding to a port of a node is an adjacent segment identifier;
• a processing unit configured to push the first label stack into the packet, wherein a top of the first label stack is the adjacent segment identifier of the first network node, determine, based on the adjacent segment identifier of the first network node, a cycle number at which the packet is forwarded, and pop out the adjacent segment identifier that is of the first network node that is in the first label stack, to obtain a second label stack;
• and
• a sending unit, configured to send, to the second network node within a period of time corresponding to the cycle number, the packet comprising the second label stack.